The Emerald Isles began as two separate land masses which fused together over 440million years ago, a Belfast born geologist has said in his new book.

Paul Lyle is author of “Between Rocks and Hard Places”, which includes scientific, historical, archaeological and mythical sources to support the claim.

According to the book, a geological line running from Shannon town in Co.Clare across the island to Drogheda in Co. Louth  marks the boundary between the two land masses.

Known as the iapetus suture zone the rocks on the northern side of the seam are different to those on the south. The rocks on the northern half show it formed on the same part of the earth as Scotland where as the rocks on the southern seam has a similar geological origin as England and Wales.

Speaking about his new book Mr Lyle said that Irish geologists are fortunate to have access to rocks across the entire range of geological time.

"We have been fortunate to be bequeathed with stunning natural wonders, such as the Giant's Causeway and the Marble Arch Caves, as well as a host of outstanding panoramas and views in a land rich in folklore myth and legend."